Tubular workpieces of the afore-mentioned kind and correspondingly associated pocket-shaped workpieces can--as a combination in each case--be a sleeve and the associated cuff, a trouser leg of a pair of trousers having a waistband and the associated waistband, a sports shirt and the associated collar, and the like. In all cases there is the problem that the tubular part has a slit which divides the border to be sewn, but that the border can no longer be extended or stretched in a straight line so that the sewing together of two such parts raises problems. Cuffs, collars, waistbands or the like, which are the pocket-shaped workpieces, are already closed on all sides by sewing and only remain open in the area into which the border of the tubular workpiece is to be inserted, whereupon the sewing together of these two parts then takes place.
The sewing together of two such workpieces, that is particularly the sewing of cuffs to sleeves by means of a sewing machine and manual guidance of the workpieces in the sewing machine, is effected in such a manner that the sewer opens the pocket-shaped workpiece, i.e. the cuff, and inserts the border of the tubular workpiece, i.e. the sleeve, the lateral edge which defines the slit in the border area being positioned in the cuff against the outer edge thereof. Then the sewer sews a partial seam. She subsequently positions the other lateral edge on the other end of the open cuff and draws the required sleeve material fullness into a fold. Subsequently the seam is completed by producing a second partial seam. The sewing of waistbands to trouser legs and of collars to sports shirts is effected in a manner which is identical in principle, there being no material fullness in the actual shirt part in the case of sports shirts. This sewing of cuffs to shirt sleeves is described in the journal of the Bekleidungstechnische Schriftenreihe, Vol. 6, pages 172, 173 and 222, "Arbeitsgestaltung in der Hemdenfertigung" by Karl Friedrich Koller and Ingrid Koch (in English: Clothing Industry Publications, Vol. 6, pages 172, 173 and 222, "Methods in shirt manufacture"). The disadvantage in this case is that the sewer needs a very long period of training. The sewing of right and left sleeves alternately requires constant rethinking. Because the joining seam between the sleeve and cuff is a visible seam, it must be designed to be particularly neat and straight. In order that the sleeves do not have different lengths, a border of equal width must be inserted into each cuff.
A method and an automatic sewing device of the type as afore-mentioned are disclosed in U.S. Pat. No. 3,779,185. Here the cuff and sleeve are mounted on cylindrical drums, i.e. sewing is effected in the form which the cuff will subsequently take on the sleeve. For this purpose the presewn cuff is retained in the area of its closed edges on a partly cylindrical supporting surface by means of clamps. Because the cuff projects over this supporting surface, it opens slightly. The cuff is opened by means of fingers which move in between the cuff layers and can swing outwardly, so that subsequently the sleeve border which is premounted on a partly cylindrical slider can be inserted in the open cuff. The lateral edge area of the sleeve is fixed on this slider by means of clamps. The material fullness which is normally present on sleeves is gathered in a pleat by means of a folding devices. After the two layers of the cuff and the edge lie firmly one upon the other, they are sewn in one operation over a circle arc segment by appropriate pivoting of the workpiece holder relative to the sewing machine. Because of the drum-shaped design of the workpiece holder the known automatic sewing device is extremely costly and the method to be used on this device is very complicated.